1. Field of the Invention
This invention relates to a polymeric composition. More particularly, this invention relates to a polymeric compound and method of making the same in which a large amount of nonionic surfactant is incorporated into a polycarboxylate backbone. Even more particularly, this invention relates to a polymeric compound and method of making the same water soluble polyacrylates are modified by the incorporation of large amounts of nonionic surfactant.
2. Description of Relevant Art
To date, little has been done in the field of water soluble polymers. A variety of partially esterified maleic acid copolymers such as those discussed in U.S. Pat. No. 3,591,608 have been synthesized. Such copolymers can be employed in aqueous solutions as emulsion stabilizers. However, partially esterified maleic acid copolymers are highly unstable in the presence of alkali as can be found in highly caustic solutions. In such solutions, these partially esterified maleic acid copolymers tend to hydrolyze to undesirable and non-usable forms. Attempts have been made to stabilize partially esterified maleic acid copolymers. In U.S. Pat. No. 4,633,485 to Scardera, maleic acid is mixed with at least one polyoxyalkylated alcohol in the presence of a free radical initiator and subsequently sulfating the product thus formed to convert a major portion of the terminal hydroxyl groups in the formed product to sulfate groups. The polymeric compound produced is useful as an anionic surfactant in aqueous systems; particularly those containing more than about 10 percent by weight of an alkali metal hydroxide.
Water soluble polymers containing acrylic acid having a molecular weight between about 1,000 and about 1,000,000 have been synthesized. These polyacrylates have been useful in a variety of applications such as thickeners, viscosity regulators, detergency builder replacements, soil suspension agents, dispersing agents, etc. Various attempts have been made to incorporate other compounds with the water soluble polyacrylate polymer. Most attempts resulted in mixtures of the desired compound with the polyacrylate polymer with little or no chemical interaction between the two materials. For example, in U.S. Pat. No. 4,490,271 to Spadini, an admixed solution was formed between a polyacrylate solution having a molecular weight between about 1000 and 20000 and a solution containing polyethylene glycol having a molecular weight between 1000 and 50,000. The mixture is particularly useful in powdered detergent compositions.
U.S. Pat. No. 3,609,069 to Renold teaches that a polymeric dispersing agent can be formed by the in situ polymerization of an appropriate monomer in the presence of nonionic detergents or surfactants. The dispersing agent produced can prevent "salting out" of builder components from liquid detergent compositions. In the Renold process, the monomers employed do not react with the selected nonionic materials during the polymerization reaction. Thus, what is formed is a physical mixture between the two constituents of limited application and practicality. While not wishing to be bound to any theory it is believed that the dispersing agent formed in Renold is a complex polymeric chain with nonionic surfactant physically trapped in voids and interstices created during polymerization. No chemical bonding occurs between the two constituents. Additionally, the Renold patent does not teach the use of low molecular-weight polymers as one of the initial reaction constituents.
It is desirable to develop and provide a polymerization product and process which will provide a modified polymer in which the modified polymer thus formed is a water-soluble polycarboxylate with an appreciable amount of nonionic surfactant chemically associated therewith.
It is also desirable that the modified polymer thus prepared be capable of functioning as an emulsion stabilizer.
It is also desirable that the polymerization process of the present invention be capable of occurring with dilute concentrations of reaction components.